Why would this dryer start normally then stop after 3 minutes? It goes completely dark --- no control panel lights at all. Resetting the circuit breaker doesn't fix it. I bought a chimney sweep kit and run the entire vent line out of the house, replaced the main circuit board with absolutely no change. Replaced all the thermistors/thermostats except the safety thermostat AP2042565 just because I missed it. No change for the better yet. After the dryer stops, the control panel comes back on in 10 minutes. Then the dryer will run on the lowest heat setting for a few minutes then stop again. When it comes back this time it will run for another 30 minutes or so then quit again. Will this safety thermostat cause the issue? If not, then what will? Thanks, Dave
ANSWER Hello Dave,
This sounds like possibly the combination of a couple of issues. First off, the symptoms sound like there is a bad connection somewhere. The issue that is irritating the first is the length of the duct. You see, a bad connection produces heat. Heat increases resistance which increases resistance. This increases amperage flow which increases heat which increases resistance. This is infinite until the electrical connection is lost entirely. The exhaust cannot exceed the equivalent of 25 feet. What this means is that each 90° elbow slows the air flow the same as 6 feet of straight ducting. So, you have to add 6 feet at every 90° turn plus the straight footage. The dryer drum is riding on felt seals. If a little too much back pressure is built up, the lint, heat, and moisture will simply blow past the drum seals back into the cabinet. This is actually where the air is taken into the unit and also where the thermostats are located. This causes the thermostats to open prematurely and this will extend the dry cycle.
The exhaust should be a 4 inch diameter rigid, non-flexible aluminum duct that is as short and straight as possible. You see, the shorter and straighter the duct is, the faster and easier it is for the unit to rid itself of the heat, lint, and moisture and the clothes will dry faster, the unit will use less electricity, and the dryer will last you longer since it isn't running a long time putting wear on the mechanical and electrical parts. All manufacturers strongly recommend against the flexible ducting whether it is plastic or the foil type. The flexible ducting crimps off the air flow too much when the unit is pushed back into place. It also holds lint which, when ignited, goes off like flash paper and will cherry inside the duct. The flexible duct will just melt through, (yes, even the foil type will just melt), and then you have the lint "cherryed up" in the floor.
A poor electrical connection is magnified by the excessive heat. I would check at the terminal block where the power cord connects to the back of the unit. All electrical connections inside the unit can be visually checked since a poor electrical connection will produce enough heat to discolor the connection.
Answered by AppliancePartsPros.com | Friday, October 05, 2012